TAK1 kinase is an essential signaling intermediate involving multiple signaling pathways including TNF, IL-1, and stress pathways. We have recently demonstrated that the targeted deletion of TAK1 in multiple epithelial tissues causes cell death and inflammatory conditions. Thus, TAK1 is critically involved in tissue homeostasis by regulating cell death. Although TAK1 regulation of pro-inflammatory signaling leading to cytokine production has been well studied, the TAK1 pathways regulating cell death remain elusive. We have identified that TAK1 regulates the level of reactive oxygen species (ROS). TAK1 binding proteins, TAB1 and TAB2, differentially participate in TAK1 signaling; TAB2 mediates cytokine-induced TAK1 activation, whereas TAB1 mediates activation of TAK1 specifically in response to stress. We hypothesize that TAK1 regulates cell survival and inflammation in vivo by modulating ROS, and that TAB1 and TAB2 regulate TAK1-cell survival signaling in response to stimulus unique to each protein. The long-term objective is to delineate the TAK1 signaling network regulating tissue homeostasis. In short- term, we aim to determine the roles of TAK1, TAB1 and TAB2 in ROS-dependent cell death pathway. Outcomes from this project will enhance our understanding of tissue homeostasis specifically regulation of ROS, cell death and inflammation, which could lead to new approaches to improve many inflammatory conditions that are associated with ROS.